1. Field of the Invention
The present invention relates to an air bag apparatus which inflates a bag body between a fixing member in a side of a vehicle body and an occupant.
2. Description of the Related Art
Conventionally, there has been suggested an air bag apparatus which is mounted on a vehicle and which inflates an air bag between a side portion of a vehicle body and an occupant of the vehicle so as to support the head of the occupant at the time of a collision in the side (a side collision) of the vehicle or the like, and absorbs the kinetic energy of the head of the occupant.
For example, the air bag apparatus is disposed in a curved interior portion extending from a front body pillar (a so-called A-pillar) positioned beside a wind shield towards the roof. The air bag apparatus is structured such that when an acceleration sensor detects a great acceleration from a side direction of the vehicle, the air bag apparatus actuates an inflator and the air bag, inflated and expanded by supplying a high pressure gas generated in the inflator into the air bag, absorbs the kinetic energy of the head of the occupant.
As a vehicle body structure for mounting such an air bag apparatus to the vehicle body, as shown in FIG. 8, there is employed a structure in which a folded air bag 14 is housed within a housing space between a reinforcement 10 curved from a front body pillar towards the roof and an interior garnish 12 fixed to the reinforcement 10 by a nut and screw 11. In this case, an aperture of a recessed portion 12A for fixing the screw in the garnish 12 is closed by a lid member 15.
The garnish 12 having the structure for mounting the air bag on the vehicle body, which is shown in a cross sectional view in a direction perpendicular to a longitudinal direction thereof in FIG. 8, has a cross section formed in a hook shape, so that a housing portion for the air bag 14 is formed therein.
The garnish 12 is structured such that a portion from the portion fixed by the screw 11 to a free end in the cross section thereof is deformed as shown by the imaginary line in the drawing at the time of the inflation and expansion of the air bag 14, so that the air bag 14 is inflated outward by allowing one side portion 12A of the garnish 12 to separate from the reinforcement 10 and to open the housing space outward.
In the air bag apparatus mentioned above, since the portion in a longitudinal direction which includes the curved portion of the garnish 12 is curved, the curved portion of the garnish 12 needs to be deformed by a large amount when the garnish 12 is deformed from having a hook-shaped cross sectional shape so as to be extended to have a linear cross sectional shape, so that a great force has been required for pushing open and deforming the garnish 12 when the air bag 14 inflates and expands.